Another reason for a shear not cutting capacity is the possibility of the piston in the air clutch leaking or the clutch
plate worn to point of replacement. To check the clutch for air Leakage, Let the flywheel come to rest, set selector switch
to "Inch" and hold the foot switch depressed. Air will now enter the clutch and, if the packing is worn or excessively dirty,
you will be able to hear air leaking past the packing. To correct this condition, dismantle the clutch, clean or replace this
packing and reassemble. To replace a worn clutch plate, see instructions on page 21.
HOLDDOWNS COME DOWN AT END OF STROKE
The holddowns come up as the ram moves upward but drop down again at the end of the stroke. This is caused by
the ram stopping past top center. To correct this, the cam for the air clutch should be adjusted to stop the ram sooner.
Loosen the two bolts on the cam and rotate it slightly so the top moves toward the ram. Retighten the bolts and cycle the
shear. Notice if the ram stops at the top. If the stopping point of the ram is erratic, this could be an indication of a worn
brake plate. See page 21.
SHEAR REPEATING
(1) Air Solenoid dirty. Dismantle and clean.
(2)
Clutch Limit Switch not contacting cam or broken. Adjust arm on Limit Switch or replace switch.
(3)
Relay in control box has burned points. Replace points or relay.
(4)
Clutch piston sticking.
Dismantle clutch and clean internally.
Apply lubricant to worm shaft and keys where
piston slides.
HOLDDOWNS DO NOT HAVE PRESSURE
First check pressure by installing a pressure gauge on the hydraulic line at the left end of the holddown bar. Bleed
the system to purge air. If the pressure is still low, check for a broken piston spring in the pump case observe if the piston
roller is following the cam throughout the cycle. Check for improper operation of the check valve in the pump case. As a
last resort increase the pressure setting on the pressure relief valve.
GENERAL MAINTENANCE
In order to provide many years of trouble-free service and accurately sheared parts from your Shear, it should be
inspected and checked on a regular basis.
(1)
Keep all bolts tight.
(2)
Check oil levels in lubricating reservoir, gear case and hydraulic pump case.
(3)
Check hydraulic holddown pressure.
(4)
Check machine level.
(5)
Check slide bearing clearances.
(6)
Check proper operation of all operating controls and electrical devices.
(7)
Turn or change dull blades.
(8)
Check parallelism of back gauge angle and reading of indicator.
(9)
When turning or changing blades, recalibrate Blade Clearance Indicators.
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